There's still lots of single NDB approaches in the US although many (most?) are supplemented by GPS approaches if nothing else is there. There's nearly always an alternative type of approach. Still, the aerodrome I'm based at only has an NDB available for a ground rather than satellite referenced approach. Interestingly the US doesn't use 'base turn/teardrop' type approach designs at all - they are all course reversal types with a 45/180 reversal turn. You could do an 80/260 reversal but I suspect everyone here stick to 45/180s.
Only last month I had to do an NDB approach to an airstrip in Georgia, complete with holding pattern & a procedure turn down to minimums. Mind you, the the typical US approach usually becomes 'vectors to intercept the final approach course' so that was a bit unusual. Was bloody glad that day that I originally trained in Oz where NDB approaches are the norm - and are a requirement for the issue of the rating.
The US has other approaches though, that don't exist in Oz or the UK: Localiser type Directional Aid, Simplified Directional Facility, Backcourse Localiser, and Localiser/NDB or VOR cross bearing fixes of the top of my head.
Still, it's fun watching the look of astonishment when I try to explain the Oz 'DME Homing & Descent' approach to US pilots.
